Printed wiring board and method for manufacturing printed wiring board

摘要

A printed wiring board and a method for manufacturing the printed wiring board in which widths of a first and a second circuit are close to each other and substantial miniaturization can be achieved. In order to achieve this object, a first circuit and a second circuit having different thicknesses are formed in the same reference plane by etching a metal-clad laminate including a conductive layer and an insulating layer. The thicker of the circuits has a clad-like configuration in which three layers, a first copper layer/a different kind of metal layer/a second copper layer, are sequentially stacked. The manufacture of the printed wiring board includes a clad composite material in which three layers of a first copper layer/a different kind of metal layer/a second copper layer are sequentially stacked as a start material, and selective etching characteristics between the layers are utilized.